[blink/mac] Support getting baseline point for showing dictionary lookup bubble.

Source/web/mac/WebSubstringUtil.mm

 /*
  * Copyright (C) 2005, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 92 matching lines @@
             [[[NSString alloc] initWithCharacters:characters.data()
                                            length:characters.size()] autorelease];
         [string replaceCharactersInRange:NSMakeRange(position, 0)
                               withString:substring];
         [string setAttributes:attrs range:NSMakeRange(position, numCharacters)];
         position += numCharacters;
     }
     return [string autorelease];
 }
 
+WebPoint getBaselinePoint(FrameView* frameView, const EphemeralRange& range, const NSAttributedString* string)
+{
+    // Compute bottom left corner and convert to AppKit coordinates.
+    // TODO(yosin) We shold avoid to create |Range| object. See crbug.com/529985.
+    IntRect stringRect = enclosingIntRect(createRange(range)->boundingRect());
+    IntPoint stringPoint = stringRect.minXMaxYCorner();
+    stringPoint.setY(frameView->height() - stringPoint.y());
+
+    // Adjust for the font's descender. AppKit wants the baseline point.
+    if ([string length]) {
+        NSDictionary* attributes = [string attributesAtIndex:0 effectiveRange:NULL];
+        NSFont* font = [attributes objectForKey:NSFontAttributeName];
+        if (font)

[esprehn, 2015/09/18 02:34:00]

We normally write this as a single statement.

if (NSFont* font = [attributes objectForKey:NSFontAttributeName])
  stringPoint.move(0, ceil(-[font descender]));

[Shu Chen, 2015/09/18 02:39:36]

Done.

+            stringPoint.move(0, ceil(-[font descender]));
+    }
+    return stringPoint;
+}
+
 namespace blink {
 
 NSAttributedString* WebSubstringUtil::attributedWordAtPoint(WebView* view, WebPoint point, WebPoint& baselinePoint)
 {
     HitTestResult result = static_cast<WebViewImpl*>(view)->coreHitTestResultAt(point);
     if (!result.innerNode())
       return nil;
     LocalFrame* frame = result.innerNode()->document().frame();
-    FrameView* frameView = frame->view();
-
     EphemeralRange range = frame->rangeForPoint(result.roundedPointInInnerNodeFrame());
     if (range.isNull())
         return nil;
 
     // Expand to word under point.
     VisibleSelection selection(range);
     selection.expandUsingGranularity(WordGranularity);
     const EphemeralRange wordRange = selection.toNormalizedEphemeralRange();
 
     // Convert to NSAttributedString.
     NSAttributedString* string = attributedSubstringFromRange(wordRange);
-
-    // Compute bottom left corner and convert to AppKit coordinates.
-    // TODO(yosin) We shold avoid to create |Range| object.
-    IntRect stringRect = enclosingIntRect(createRange(wordRange)->boundingRect());
-    IntPoint stringPoint = stringRect.minXMaxYCorner();
-    stringPoint.setY(frameView->height() - stringPoint.y());
-
-    // Adjust for the font's descender. AppKit wants the baseline point.
-    if ([string length]) {
-        NSDictionary* attributes = [string attributesAtIndex:0 effectiveRange:NULL];
-        NSFont* font = [attributes objectForKey:NSFontAttributeName];
-        if (font)
-            stringPoint.move(0, ceil(-[font descender]));
-    }
-
-    baselinePoint = stringPoint;
+    baselinePoint = getBaselinePoint(frame->view(), wordRange, string);
     return string;
 }
 
 NSAttributedString* WebSubstringUtil::attributedSubstringInRange(WebLocalFrame* webFrame, size_t location, size_t length)
 {
+    return WebSubstringUtil::attributedSubstringInRange(webFrame, location, length, nil);
+}
+
+NSAttributedString* WebSubstringUtil::attributedSubstringInRange(WebLocalFrame* webFrame, size_t location, size_t length, WebPoint* baselinePoint)
+{
     LocalFrame* frame = toWebLocalFrameImpl(webFrame)->frame();
     if (frame->view()->needsLayout())
         frame->view()->layout();
 
     Element* editable = frame->selection().rootEditableElementOrDocumentElement();
     if (!editable)
         return nil;
     const EphemeralRange ephemeralRange(PlainTextRange(location, location + length).createRange(*editable));
     if (ephemeralRange.isNull())
         return nil;
 
-    return attributedSubstringFromRange(ephemeralRange);
+    NSAttributedString* ret = attributedSubstringFromRange(ephemeralRange);

[esprehn, 2015/09/18 02:34:00]

don't abbreviate. 

NSAttributedString* result = ...;

[Shu Chen, 2015/09/18 02:39:36]

Done.

+    if (baselinePoint)
+        *baselinePoint = getBaselinePoint(frame->view(), ephemeralRange, ret);
+    return ret;
 }
 
 } // namespace blink